<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>2448-5691</journal-id>
<journal-title><![CDATA[Mundo nano. Revista interdisciplinaria en nanociencias y nanotecnología]]></journal-title>
<abbrev-journal-title><![CDATA[Mundo nano]]></abbrev-journal-title>
<issn>2448-5691</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Instituto de Ciencias Aplicadas y Tecnología]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2448-56912013000200029</article-id>
<article-id pub-id-type="doi">10.22201/ceiich.24485691e.2013.11.50002</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Observación de capas de grafeno mediante contraste óptico y dispersión Raman]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Bautista Flores]]></surname>
<given-names><![CDATA[Claudia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Sato Berrú]]></surname>
<given-names><![CDATA[Roberto Ysacc]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Mendoza López]]></surname>
<given-names><![CDATA[Doroteo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales ]]></institution>
<addr-line><![CDATA[ D. F.]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Nacional Autónoma de México Centro de Ciencias Aplicadas y Desarrollo Tecnológico ]]></institution>
<addr-line><![CDATA[ D. F.]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2013</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2013</year>
</pub-date>
<volume>6</volume>
<numero>11</numero>
<fpage>29</fpage>
<lpage>39</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2448-56912013000200029&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2448-56912013000200029&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2448-56912013000200029&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: En este trabajo hemos usado la técnica de contraste óptico como herramienta de identificación preliminar y sencilla de capas de grafeno, la cual es más simple en comparación con la propuesta de otros autores y es validada con espectroscopia Raman. Para ello obtenemos grafeno y pocas capas de grafeno por exfoliación mecánica de grafito Kish. Adquirimos imágenes digitales, a través de un microscopio óptico, de las diferentes muestras depositadas sobre un sustrato de silicio con una película de óxido de silicio de 306.2 nm. Con un programa de análisis de imágenes adquirimos la componente verde de los números RGB, tanto de la muestra como del sustrato; con ello, calculamos el contraste óptico y determinamos el número de capas de grafeno. Logramos determinar de una a cuatro capas de grafeno.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: We used the optical contrast technique to identify layers of graphene, in a simpler way in contrast with other authors; this technique was validated by Raman spectroscopy. Layers of graphene were obtained by mechanical exfoliation of Kish graphite, and were deposited on silicon substrate with a 306.2 nm film of silicon oxide. Digital images of these samples were taken to use green component of the RGB numbers in the optical contrast calculation. We can identify from one to four layers of graphene.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Contraste óptico]]></kwd>
<kwd lng="es"><![CDATA[capas de grafeno]]></kwd>
<kwd lng="es"><![CDATA[electroscopía Raman]]></kwd>
<kwd lng="en"><![CDATA[Optical contrast]]></kwd>
<kwd lng="en"><![CDATA[layers of graphene]]></kwd>
<kwd lng="en"><![CDATA[Raman spectroscopy]]></kwd>
</kwd-group>
</article-meta>
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